Hi there,

Right now I'm using this formula:

=INDEX(Last_Inspection_Reported,MATCH(1,(Last_Insp ection_Bus=$A4)*(Last_Inspection_ID="CV"),0))

This is repeated down a list quite a long ways. I only really need this
calculation every 12th time to avoid duplicate data, but I can handle
leaving it as is if it will slow down the calculation time.

My question is this: If I change my formula to:

=If($D4=1,INDEX(Last_Inspection_Reported,MATCH(1,( Last_Inspection_Bus=$A4)*(Last_Inspection_ID="CV") ,0)),"")

Will this speed up or slow down the calculation time? Column D contains
a repeating series of numbers from 1-12, with each new series
containing a new dataset; thus I only need the results once, BUT this
is operating from a Query/named range, so the formula needs to be in
there for future expansion/retraction of the data, so its not possible
to just enter the formula only on the rows containing a "1" in column
D.

Thanks for your opinions,
-Sean